Achilles mourning the death of Patroclus. In Greek mythology, Achilles was a Greek hero of the Trojan War, the central character and the greatest warrior of Homer's Iliad. Patroclus was the son of Menoetius, grandson of Actor, King of Opus, and was Achilles' beloved comrade and brother-in-arms. The exact nature of Achilles' relationship with Patroclus has been a subject of dispute in both the classical period and modern times. Mezzotint by William Wynne Ryland after Angelica Kauffman, 1777.